Quantcast
ZME Science
  • News
  • Environment
  • Health
  • Future
  • Space
  • Features
    Menu
    Natural Sciences
    Health
    History & Humanities
    Space & Astronomy
    Technology
    Culture
    Resources
    Natural Sciences

    Physics

    • Matter and Energy
    • Quantum Mechanics
    • Thermodynamics

    Chemistry

    • Periodic Table
    • Applied Chemistry
    • Materials
    • Physical Chemistry

    Biology

    • Anatomy
    • Biochemistry
    • Ecology
    • Genetics
    • Microbiology
    • Plants and Fungi

    Geology and Paleontology

    • Planet Earth
    • Earth Dynamics
    • Rocks and Minerals
    • Volcanoes
    • Dinosaurs
    • Fossils

    Animals

    • Mammals
    • Birds
    • Fish
    • Reptiles
    • Amphibians
    • Invertebrates
    • Pets
    • Conservation
    • Animals Facts

    Climate and Weather

    • Climate Change
    • Weather and Atmosphere

    Geography

    Mathematics

    Health
    • Drugs
    • Diseases and Conditions
    • Human Body
    • Mind and Brain
    • Food and Nutrition
    • Wellness
    History & Humanities
    • Anthropology
    • Archaeology
    • Economics
    • History
    • People
    • Sociology
    Space & Astronomy
    • The Solar System
    • The Sun
    • The Moon
    • Planets
    • Asteroids, Meteors and Comets
    • Astronomy
    • Astrophysics
    • Cosmology
    • Exoplanets and Alien Life
    • Spaceflight and Exploration
    Technology
    • Computer Science & IT
    • Engineering
    • Inventions
    • Sustainability
    • Renewable Energy
    • Green Living
    Culture
    • Culture and Society
    • Bizarre Stories
    • Lifestyle
    • Art and Music
    • Gaming
    • Books
    • Movies and Shows
    Resources
    • How To
    • Science Careers
    • Metascience
    • Fringe Science
    • Science Experiments
    • School and Study
    • Natural Sciences
    • Health
    • History and Humanities
    • Space & Astronomy
    • Culture
    • Technology
    • Resources
  • Reviews
  • More
    • Agriculture
    • Anthropology
    • Biology
    • Chemistry
    • Electronics
    • Geology
    • History
    • Mathematics
    • Nanotechnology
    • Economics
    • Paleontology
    • Physics
    • Psychology
    • Robotics
  • About Us
    • About
    • The Team
    • Advertise
    • Contribute
    • Privacy Policy
    • Contact
No Result
View All Result
ZME Science

No Result
View All Result
ZME Science

Home → Health → Diseases

Beware of infections in tropical waters – Flood hit areas more vulnerable

Bala Murali Krishna Yelchuri by Bala Murali Krishna Yelchuri
November 22, 2012
in Diseases, Health

schistosomiasis

Beware of snails before you swim in shallow waters of tropical countries such as India. You can avoid parasitic worm infections caused by the snails, according to a new study. The risk is more in flood hit areas, such as Andhra Pradesh which requires a ground survey to prevent infections which could be detected through urine or stool test.

The scientists caution people in Africa, Asia and South America where access to clean water and good sanitation facilities are scarce.

“Snails that live in tropical freshwater in these locations are intermediaries between disease-causing parasitic worms and humans”, scientists claim.

The worms’ infectious larvae emerge from the snails, cruise in shallow water, easily penetrate human skin and mature in internal organs.

The result is schistosomiasis, the second most socio-economically devastating disease after malaria. As of 2009, 74 developing nations had identified significant rates of schistosomiasis in human populations. There has been much debate about how best to prevent the disease, says Charles King, a physician and researcher at Case Western Reserve University in Cleveland, Ohio.

“Beyond that,” he asks, “how long should treatment last once someone has schistosomiasis?”

“Current guidelines focus on suppressing the disease’s effects by limiting the infection during childhood,” says King. “But that may not be enough to cure it or to prevent re-infection, leaving children still at risk for stunted growth and anemia,” he adds.

King and colleagues recently published results of a study of long-term treatment of schistosomiasis in the journal PLOS Neglected Tropical Diseases. The team’s work is funded by the National Science Foundation (NSF)-National Institutes of Health (NIH) Evolution and Ecology of Infectious Diseases (EEID) program. At NSF, the EEID program is supported by the Directorate for Biological Sciences and Directorate for Geosciences. At NIH, it’s supported through the Fogarty International Center.

Schistosomiasis is usually treated with a single dose of the oral drug praziquantel.

Current prevention guidelines are ineffective

World Health Organization (WHO) guidelines set forth in 2006 recommend that when a village reports that more than 50 percent of its children have parasite eggs in their urine or stool– a clear sign of schistosomiasis– everyone in the village should receive treatment. When 10 to 50 percent of children are affected, say the guidelines, only school-age children should be treated–every two years. With less than 10 percent, mass treatment is not suggested.

But because of the long-term health effects of schistosomiasis, says King, “we now think it’s better to provide regular yearly treatment.”

He and scientists Xiaoxia Wang, David Gurarie and Peter Mungai of Case Western Reserve University; Eric Muchiri of the Ministry of Public Health and Sanitation in Nairobi, Kenya; and Uriel Kitron of Emory University in Atlanta, Georgia, used data collected in 10 villages in southeastern Kenya to run advanced models of village-level schistosomiasis transmission.

They scored the number of years each of the 10 villages would be projected to remain below a 10 percent infection level during a simulated 10-to-20-year treatment program. All strategies that included an initial four annual treatments reduced community prevalence of the disease to less than 10 percent. Programs with gaps in treatment, however, didn’t reach this objective in half the villages.

At typical levels of treatment, the researchers found, current WHO recommendations could not achieve full suppression of schistosomiasis.

“With more aggressive annual intervention that lasts at least four years,” says King, “some communities might be able to continue without further treatment for 8 to 10 years.

“But in higher-risk villages, repeated annual treatment may be necessary for an indefinite period–until the eco-social factors that foster the disease [such as poor wastewater treatment] are removed.”

schistosomiasis world map In high-risk places, ongoing surveillance for the disease and annual drug treatment, the scientists say, need to become the mainstays of control. In short, these villages require what they call “re-worming after de-worming.”

But what happens if townspeople move to a more arid location, one with less freshwater and fewer snails? In drier landscapes, schistosomiasis is a rare event that happens only during floods. Response to treatment therefore may be much better. Unless or until another flood occurs. Although drier locales carry less risk for the disease, they’re by no means free and clear. Even in arid locations, people need to get treated more than once to get rid of the parasites.

“This research demonstrates the value of understanding where disease-causing organisms are in the environment,” says Sam Scheiner, NSF program officer for EEID.

“Such knowledge can reduce human diseases much more effectively and at a lower cost than simply focusing on treatment.”

The best goal, says King, is complete eradication of schistosomiasis.

To achieve that, scientists need to determine what makes a “wormy village,” how often therapy is needed to prevent disease in such locations–and what can be done to change the environment such that a high-risk village becomes a low-risk one.

Was this helpful?


Thanks for your feedback!

Related posts:
  1. Researchers zero in on why older people are more vulnerable to influenza — and maybe other infections as well
  2. Whales and sharks sightings increase around NY waters, in response to cleaner waters
  3. Tall trees in tropical forests are less vulnerable to drought
  4. Jesus lizard ancestor skimmed the tropical waters of Wyoming, 48 million years ago
  5. NASA Satellite Reveals Tropical Storm Andrea’s Towering Thnderstorms – Tropical Storm Warning in effect
Tags: malariaschistosomiasis

ADVERTISEMENT
  • News
  • Environment
  • Health
  • Future
  • Space
  • Features
  • Reviews
  • More
  • About Us

© 2007-2021 ZME Science - Not exactly rocket science. All Rights Reserved.

No Result
View All Result
  • News
  • Environment
  • Health
  • Future
  • Space
  • Features
    • Natural Sciences
    • Health
    • History and Humanities
    • Space & Astronomy
    • Culture
    • Technology
    • Resources
  • Reviews
  • More
    • Agriculture
    • Anthropology
    • Biology
    • Chemistry
    • Electronics
    • Geology
    • History
    • Mathematics
    • Nanotechnology
    • Economics
    • Paleontology
    • Physics
    • Psychology
    • Robotics
  • About Us
    • About
    • The Team
    • Advertise
    • Contribute
    • Privacy Policy
    • Contact

© 2007-2021 ZME Science - Not exactly rocket science. All Rights Reserved.

Don’t you want to get smarter every day?

YES, sign me up!

Over 35,000 subscribers can’t be wrong. Don’t worry, we never spam. By signing up you agree to our privacy policy.

✕
ZME Science News

FREE
VIEW